Envelope opening machine



June 20, 1939. J ER ET AL 2,163,026

ENVELOPE OPENING MACHINE Filed Oct. 7, 1957 s Sheets-Sheet 1 June 20,1939.

E. J. DUMMER ET AL ENVELQPE OPENI NG MACHINE Filed Oct. 7, .1937

3 Sheets-Sheet 2 INVENTORS June 20, 1939. E J. DUMMER El AL 2,163,026

ENVELOPE OPENING MACHINE Filed Oct. 7, 1937 3 Sheets-Sheet 3 9 9 3'8lINVENTORS Patented June 20, 1939 PATENT OFFICE ENVELOPE OPENING MACHINEEdward J. Dummer and Azel Gay, Rochester,

N. Y., assignors to Multipost Company, Rochester, N. Y., a corporationof New York Application October 7,

4 Claims.

Our present invention relates to paper feeding and cutting machines andmore particularly to envelope or mail opening machines of the type inwhich the letters either piled or singly may be run rapidly through andone of their marginal edges neatly slit to just remove the fold withoutinjuring the contents, and it has for its object to provide a simple,eflicient and improved machine of this character that may beconveniently .10 operated at high speed and capacity and yet with suretyof accurate performance. The improvements are directed more particularlyin connection with cutters, an envelope edge guide in the feeding ofenvelopes thereto and an envelope conveyor or feeding device, to a novelform of presser foot having characteristics in the functioning of whichit holds the particular envelope being operated upon and so conveyed inproper contact with the conveyor and with the guide regardless of thethickness of the envelope within certain limits and with due regard forthe safety ofits contents. To these and other ends, the inventionresides in certain improvements and combinations of parts, all as willbe hereinafter more fully described, the novel features being pointedout in the claims at the end of this specification.

In the drawings:

Fig. 1 is a front elevation of a letter opening machine constructed inaccordance with and illustrating one embodiment of our invention;

Fig. 2 is a top plan view thereof;

Fig. 3 is a vertical section taken substantially on the line 3-3 of Fig.1 and viewed in the direction of the arrows;

Fig. 4 is an enlarged detail sectional end view of the presser footwhich allows the envelopes to climb the belt only one at a time;

Fig. 5 is an enlarged front view of the knives and the edge guide, theintervening parts being removed;

Fig. 6 is an enlarged fragmentary end view of the upper portion of themachine showing the presser foot of this invention;

Fig. 7 is a fragmentary front view of the upper feed portion of themachine on the scale of Fig. 6 and illustrating in side elevation thepresser foot of this view;

Fig. 8 is a fragmentary sectional view taken transversely through thepresser foot and an envelope held thereby substantially on the line 8-8of Fig. 7

Fig. 9 is an end view of a modified form of presser foot; 1

Fig. 10 is a detail front view of a further modi- 1937, Serial No.167,773

fied form of presser foot detached from its mounting, and

Fig. ll-is an end View thereof looking from the delivery end of themachine.

Similar reference numerals throughout the several views indicate thesame parts.

This application is a continuation in part of our prior application,Ser. No. 117,486, filed Dec. 24, 1936, entitled Envelope openingmachine, in which parent application several features looking to theobjects herein generally expressed are embodied. A descriptionsufficient to give a clear understanding of the present inventionrequires a repetition of the showing in some respects of the aforesaidparent application.

Referring more particularly to the drawings, I indicates a preferablycastbase I having end walls I anda partition-like central framework 2rising therefrom. At the front is suitably secured a cover plate 3 andat the rear a cover plate 4 together constituting a casing within whichthe interior mechanism is housed. At the front a shelf-like plate 5constitutes the bed along which the envelopes are fed and operated upon.Rising from the rear wall of this bed plate atthe left end thereof inFig. l is a flange 6 constituting a general rear guide wall. Atransversely extending vertical plate 1 has a flange by which it issecured to the frame 2 at 8 and constitutes a gate beneath which theenvelopes are fed. They are stacked on this left hand or feed end of thebed plate 5 in an inclined pile, the regularity of which is establishedby the guide wall 6 and the said gate 1. The downward inclination of thefeed of the lower envelope is established by a shed 9 secured to thetable by a screw i0 passing therethrough and into a lug H on theadjacent base end l At the right hand end of the table, the frame 2 isprovided with a bearing l2 in which turns a shaft 13 having at its rearend a driven pulley I4 and belt [5 by which it is turned from thedriving pulley l6 of a motor ll mounted on the base. The shaft l3extends through the frame partition 2 and at its forward end is a hub [8against the rear side of which is clamped securely by a nut 19 aslitting knife 20. Against the front side of the hub is similarlysecured by a nut 2| 2. grooved pulley 22. Another grooved idler pulley23 is suitably mounted on the frame partition 2- and over the twopulleys passes an endless feed belt 25. This feed belt is preferably ofrubber and circular in cross section. Its upper reach 26 travels in slot21 on the bed plate 5 and projects just partially above the same so asto take sure frictional contact with an envelope on the bed while thelatter is still maintained in a substantially flat condition.

Above the bearing I2 is a similar bearing 28 on the frame 2 containing astud shaft 29. On the outer or forward end of this stud is a hub 30against which there is clamped by a nut 3| an upper companion slittingknife 32 cooperating in the overlapping manner best shown in Figs. 3 and5 with the driven knife 20. A housing 20 open sufficiently at the bottomonly to admit a guiding means and the envelopes, covers and protectsthis knife, the same being held to the frame wall 2 by screws 20 Thestud 29 is hollow and contains a spring 33 that reacts against a plate34 secured to the end of the bearing box by two screws 35. The knife 32is thus urged forwardly continuously by the spring against the drivenknife 20 to itself be frictionally driven by the latter.

As best shown in detail in Fig. 5, an extension 36 on the end of theback plate or guide 6 of the bed plate 5 projects toward the knives andhas a tapered end 31 that enters between them at their intersectionrunning as closely as possible to the bite or cutting point of theblades. This extension is V-shaped in cross section, as shown also inthe other figures, but the bottom at the inside apex is definitely flat,as indicated at 38, lies in the plane of the guide wall 6 and this planeis sufficiently back of the cutting plane defined by the contactingsurfaces of the knives to cut off the fold of the envelope edge back thedesired distance. The lower plate 39 of the edge guide inclinesdownwardly outwardly to contact with the bed plate 5 while itslongitudinal projection toward the feed end of the machine is given acompound curve into which the lateral inclination merges, whereby italso inclines downwardly at the receiving end to meet the surface of thebed plate and form a ramp portion 40 up which the envelopes slide toenter the edge guide against the wall 38. The upper plate of the V atthe corresponding end has a share portion 4| Where it joins the plate 6for a similar purpose.

As so far described, in operation, the undermost letter of a pilesquared against the back wall 6 and the gate 1 touches or is urged bythe operator against the belt 25. It is carried under the gate and thefrictional hold of the belt thereon causes it to overcome the retardinginfluence of a spring finger 42 on the far side of the gate having anotch 43 therein (Fig. 4) to accomlmodate the belt. The finger has arounded lower edge which, however, arrests the envelope next above untilthe first one, whose frictional contact might otherwise carry it withit, has passed on. This adjacent one in turn contacts the superiorfriction of the feed belt and is next fed forward. The latter carrieseach envelope along the edge guide through the knives which slit thefold thereof and then passes out at the right end of the machine inopened condition.

The said retarding finger 42 is mounted on a shaft 44 extending betweenthe securing flange and a front flange 45 of the gate plate 1 and ispressed downwardly by a spring 46 coiled about such shaft. A lug 41 onthe finger carries a stop screw 48 that bears against a lug 49 on thegate to limit the downward thrust of the finger with reference to thebelt and to the nature of the mail matter that is passing through.

It is, of course, important that as the envelope enters the knives itsedge should be firmly and evenly pressed against the wall 38 of the edgeguide so that the fold thereof will be uniformly and evenly sheared offto exactly the desired extent. This is insured by the followingprovisions: In the first place, the direction of travel of the upperreach 26 of the belt is not strictly longitudinally of the bed butconverges inwardly from. pulley 23 to pulley 22. In addition to this,the axis of pulley 23 is cooked in two planes intersecting the plane ofthe axis of pulley 22, as clearly appears, that is, the stud is tilteddownwardly and also laterally bringing the pulleys out of line on twoangles. The result is that the reach 26 of the belt twists or rotates onits own geometrical axis toward the knives as it passes from the onepulley to the other in the feeding direction. Its frictional efiect onthe envelope is, therefore, both to convey it in a straight path and tourge it laterally toward the knives and against the edge guide 36.

At the cutting point, the envelope is held to the knives, in oneconstruction, by a presser foot that comprises an elongated foot portion61 pivoted at 68 under the influence of a spring 69 that thrusts ityieldingly downward to a normal position limited by a screw 10 engaginglug 51. However, a rounded heel H at the rear starts very close to thefinger 42 and the foot extends from there up to the median line of theknives with the toe preferably a little beyond that point, as indicatedat 12 in Fig.7. The smooth flat undersurface 13 is inclined transverselydownwardly toward the edge guide 36 and the cutting plane.Longitudinally, this same surface is in parallel with the upperprojecting reach 26 of the cylindrical feed belt 25 and normally butslightly spaced therefrom, so that even a thin envelope will be clampedlightly between the foot and the belt. In other words, in cross section,as in Fig. 8, the under engaging surface of the foot is not horizontalbut is cocked tangentially of the surface of the belt beneath theenvelope, which latter is indicated at E in the figure referred to. Theresult is to amplify the frictional grip that the rotating belt exertsagainst the envelope in urging it against the guide and into the cuttingplane. The inner or depressed longitudinal. edge dips the envelope atthe point. where reference letter E is attached in Fig. 8 downwardlyaround and beyond the belt while the lower plate 39 of the guide 36directs it upwardly to the apex wall 38. Thus, an enlarged frictionalcontact surface of the belt is brought into play and this inner edge ofthe presser foot so holds the envelope to the belt practicallycontinuously along the edge guide 36, being definitely between it andthe belt. Particularly with long envelopes, the tendency is for the rearend to twist or slew away from. the cutting plane as it reaches theknives, as previously mentioned, but with this foot 61 such rear end isheld in proper position to the very last of the cut.

In Fig. 9, a modification is shown in which a presser foot 56 similarlymounted and similarly regulated is composed of a wide sheet metalstamping that presents a greater expanse of un-- der inclined surface 59above the belt and toward the edge guide and the cutting plane.

In conclusion, attention is called to the functional showing of Fig. 8as indicative of the advantages inherent in all forms of the presentinvention. The transversely rotating. belt. 26 in addition to itsinclination of feed urges the envelope E toward the guide 36. This guideis somewhat near the elevation of the carrying surface of the belt.Nevertheless, its lower portion 15 39 reaches down below the belt. Thepresser foot 13 has an inclination, as stated, downwardly over the belttoward this lower guide portion 39. As the envelope is urged laterallytoward the guide, it must take the curve shown insuring gripping contactwith the belt. In addition, as such envelope is forced between the beltand the inclined presser foot '53, the latter has a tendency to urge thebulky contents of the envelope toward the interior of the latter andaway from the cutting plane of the knife blades. In this way, the knivesoperate only upon the envelope on a marginal edge free of the contentsthat otherwise might be crowded into the sphere of action of the knives.

In Figs. 10 and 11, a presser foot block or shoe (5 is shown as afurther modification, the under side of which is inclined at 15 in thesame way with reference to the conveyor belt and the table 5. However,it is articulated centrally at H upon a presser foot arm 18 by means ofa pivot bolt 19 pinned to the lugs 89 of the said arm. A central lug 8!on the foot takes the pivot while other lugs 82 constitute saddles forthe contact of a leaf spring 83 that passes through the pivot bolt 19 solocked against rotation. The said arm 18 has a bearing 84 for the stud58, a lug 85 for a limiting screw and a shoulder 86 to take the pressureof a spring like spring 69, all as before.

The point of this construction is that, while in a footof the charactershown in Fig. 7 the raising of the heel H by the passage of an envelopethereunder will greatly increase the raising of the toe 12 withreference to parallelism to the conveyor belt, in this embodiment ofFigs. 10 and 11 the shoe portion 15 of the foot will tilt from itscenter and tend to maintain parallelism with the belt under theinfluence of the leaf spring. A useful function thereof is that in casea thick envelope precedes a thin one in travel over the conveyor, or athin envelope precedes a thick one, the thick envelope will not hold thepresser foot out of contact with the thin one altogether and hence leavethe thin one without any pressure against the belt at all. In otherwords, the shoe 15 of the foot will become adaptable and transmit atleast part of its pressure to the thin one of said envelopes while alsoriding on the thick one.

We claim as our invention:

1. In an envelope opening machine, the combination with a bed plate, aknife arranged angularly thereto, an endless belt for feeding envelopesalong the bed and an edge guide for the envelopes associated with theknife to direct the edge of an envelope in the cutting plane thereof, ofa yielding rocking presser foot adapted to engage the edge portion ofthe envelope at the cutting point, said presser foot being arranged inopposition to the belt and having its under envelope contacting surfaceflat and inclined transversely downwardly toward the cutting planeinsuch manner that it does not hug the belt but is purely tangentialthereto.

2. In an envelope opening machine, the combination with a bed plate, aknife arranged angularly thereto, an endless belt for feeding envelopesalong the bed and an edge guide for the envelopes associated with theknife to direct the edge of an envelope in the cutting plane thereof, ofa yielding rocking presser foot adapted to engage the edge portion ofthe envelope at the cutting point, said presser foot being arranged inopposition to the belt and having its under envelope contacting surfaceflat and inclined transversely downwardly toward the cutting plane, anda lower inclined plate on the edge guide sloping reversely downwardlytoward the belt to receive the envelope from the incline of the presserfoot.

3. In an envelope opening machine, the cornbination with a bed plate, aknife arranged angularly relatively thereto, an endless belt for feeding envelopes along the bed and an edge guide for the envelopesassociated with the knife to direct the edge of an envelope in thecutting plane thereof, of a yielding rocking presser foot adapted toengage the edge portion of the envelope at the cutting point, saidpresser foot being arranged in opposition to the belt and having itsunder envelope contacting surface flat and inclined transverselydownwardly toward the cutting plane, and a pivoted supporting arm forthe presser foot articulated therewith at a substantially central pointso that the presser foot may equalize its pressure against the belt asbetween intervening thick and thin envelopes riding between them.

4. In an envelope opening machine, the combination with a bed plate, aknife arranged angularly relatively thereto, an endless belt for feedingenvelopes along the bed and an edge guide for the envelopes associatedwith the knife to direct the edge of an envelope in the cutting planethereof, of a yielding rocking presser foot adapted to engage the edgeportion of the envelope at the cutting point, said presser foot beingarranged in opposition to the belt and having its under envelopecontacting surface flat and inclined transversely downwardly toward thecutting plane, a pivoted supporting arm for the presser foot articulatedtherewith at a substantially central point so that the presser foot mayequalize its pressure against the belt as between intervening thick andthin envelopes riding between them, and a spring acting between thesupporting arm and presser foot to transmit a balancing pressure on thetwo ends of the presser foot.

EDWARD J. DUMMIER. AZEL GAY.

